In the last six cantos of the Purgatorio, Dante describes the Earthly Paradise upon the summit of the Mountain of Purgatory. It is the most allegorical, and therefore the most difficult and fascinating, part of the Commedia. A. F. Ozanam called it the ‘apex’ of the Commedia.

Six times in the course of it the poet tells us that this was the ancient Garden of Eden, the ‘nest’ of the human race. And the emphasis he thus lays upon this identity of place must give us the right key to the interpretation of the wonderful scenes he there witnesses and takes part in. We propose, therefore, to follow the example of the older commentators who saw their theological and spiritual, rather than their political, signification. Here as elsewhere it is necessary to remember that the poet was, primarily, not a politician but a theologian.

In the closing lines of the twenty-seventh canto, Virgil has addressed to Dante his famous last words, ‘Now is thy will free, upright and whole; therefore with crown and mitre I make thee sovereign over thyself.’ And the twenty-eighth canto opens with that most bewitching description of the loveliness of the ‘divine forest,’ its foliage and its birds, which Ruskin quotes in Modern Painters, where he points out the significance of the contrast between its freedom and joyousness and the ‘wild and gloomy wood’ of the Inferno, which even in remembrance, said the poet, still dismayed him.